214 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



scarcely greater than the width of the iuterorbital space. Preorbital 

 bone large, oblong, conspicuous, and silvery. Mouth rather small, hor- 

 izontal, the lower jaw included, the edge of the premaxillary below the 

 level of the eye, the maxillary not reaching to the vertical from the 

 front of the orbit. Barbel quite small. Snout boldly and abruptly de- 

 curved much as in C. ajuhlops, the tip of the snout thickened, forming a 

 sort of pad. Lateral line decurved. Eows of scales along the back 

 converging behind the dorsal Avhere the upper series run out, as in 

 Minniliis cornutus. Fins rather higher and more falcate than in G. 

 biguttatiis. The dorsal lin inserted well forward, over ventrals. Pec- 

 toral fins pointed, not reaching ventrals, ventrals not reaching vent. 

 Teeth 4-4, hooked, without grinding surface. Translucent greenish 

 above; sides and below brilliantly silvery; cheeks and opercles with a 

 bright silvery lustre; fins plain ; a slight plumbeous lateral shade. Head 

 4^; depth 4. D. 8; A. 8; scales 5-42-4. L. 5 inches. Falls of the Ohio. 

 (Jordan, Proc. U. S. Nat. Mus. 1879, 238.) 



331. C. amblops (Kaf.) Gvd.— Silver Chub. 



Body rather slender, somewhat heavy anteriorly, not much com- 

 pressed. Head large, somewhat flattened and broad above. Eye very 

 large, longer than snout and longer than iuterorbital space, 3 in head. 

 Mouth horizontal, subinferior, and rather small. Muzzle bluntly de- 

 curved. Upper lip below level of orbit, maxillary not reaching the line 

 of the front of the orbit. Barbel evident. Fins moderate. Lateral 

 line somewhat decurved. Sixteen scales before dorsal. Color translu 

 cent greenish above ; scales somewhat dark-edged ; sides with a bright 

 silvery band, which overlies dark pigment, so that sometimes a plumbe- 

 ous or even blackish band appears ; a dark band through eye around 

 snout ; males v/ithout tubercles or red coloration. Head 4 ; depth 5. 

 D. 8; A. 7 ; scales 5-38-4; teeth 1, 4-4, 1. L. 2-4 inches. Ohio Valley 

 and southward. Southern specimens (var. ivinchelli) have the head 

 narrower and the barbel rather shorter. 



{Rutilus amblops Rat". Ichth. Oh. 1820, 51: fHjjbopsis gracilis Agassiz, Amer. Journ. 

 Sci. Arts, 1854, 358 : Gobio i^n'nalis and Ilybopsis ivinchelli Grd. Proc. Acad. Nat. Sci. 

 Phila. 1856, 188, 211: Ccralichthys lujalinus Cope, Journ. Acad. Nat. Sci. 1809, 236: 

 Ceratichthys hyalinus Giiuthor, vii, 179 : Nocomis amblops Jordan, Ann. Lye. Nat. Hist. 

 :N. Y. 1876, 328.) 



4^32. C reibrifroMS Jordan. 



General form of the preceding. Head loug, narrower than in the pre- 

 ceding, longer than iu the next. Eye moderate, 3i^-3i in head, wider than 

 the iuterorbital space. Mouth smaller, inferior, overhung by the bluntly 



